Motor-controlling system.



c; T. HENDERSON. MOTOR CONTROLLING SYSTEM. APPLICATION FILED IAB.14 1907.

Patented am. 19, 19081 WlTNESSESi (7W7; 125.5%Jm

ATTORNEY G. T. HENDERSON. MOTOR CONTROLLING SYSTEM.

APPLICATION IILIZD MAB. 14IL 1907.

9033288. Patented Nov. 10, 1908.

2 SHEETS-SHEET 2.

INVENTOR an fismy ATTORNEY fore it comes to a stop.

U ITED PATENT ormon.

CLARK T. HENDERSON, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER-HAMMER MANUFACTURING COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF WIS- GONSIN.

To all whom it may concern:-

a citizen ofthe United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Motor-Controlling Systems,-of which the following is a full, clear, concise, and exact description, reference being had' to the accompanying drawing, forming a part of this specification.

My invention'relates to improvements in systems for automatically controlling electric motors a'ndhas particular reference to improvements in systems for automatically controlling electric motors adapted to operate centrifugal or turbine pumps and the like.

By my improved system the motor is antomatically started and stopped under predetermined conditions. As soon as the pressure on the volume of water has been increased to the proper amount, the motor is automatically sto ped.

My invention also provides for automatically slowing down the speed of the motor be- This feature is espe cially advantageous under certain, conditions where the motors operate a pump acting against a certain head of water. Under these conditionsordinarily, when the power is suddenly shut oftfrom themotor driving the pum the head of water above the check valve wi I settle back on the valve with a destructive hammer blow. By automatically slowing down the speed of the motor this hammer blow is avoided.

For the purpose of disclosing my invention I have'illustrated in the accompanying dlrawings, systems embodying the features t iereo Figure 1 shows a diagrammatic view of the.

Specification of Letters Patent.

Application riled March 14, 1907. Serial No. 362,385.

MOTOR-CONTROLLING SYSTEM.

' Patented Nov. 10, 1908.

bridging contacts 5. The arm is arranged to be engaged by the bifurcated ends 6 and 7 of a weighted lever 8, which in turn is op erated by a lever 9 arranged to engage pins 10 and 11 formed on the lever 8 and moved by the'connection 12 with the float 13 in the tank 3. This connection may be in the form of a chain having at one end thereof: a weight 14 arranged to counterbalance the weight of the float 13 and connected to the end of the lever 9. In operation, as the water falls in the tank 3, the end of the lever 9 will be raised and through its engagement of the pin 11, will move the weighted lever to the left. As soon as the lever passes its center the Weight will throw it to its ex- .treme opposite position, and the arm 6 will engage the lever 4c, snapping the same over to bridge' the contacts ofthe switch. By this construction I am enabled to obtain a quick make and-breakbetween the contacts of the switch.

Thearmature 15 of the. motor has included in the circuit thereof, a resistance 16 controlled by the arm 17. The speed at which the arm moves is controlled by a dashpot 18 which is so constructed 'thatit 4 retards the movement of the arm in both directions. The arm 17 is operated by a solenoid 19:-v The field 20 of the motor has included 'in the circuit thereof, a resistance 21 posite position, and the bifurcation 6 will engagethe'a-rm 4, snapping it over until the bridging contacts 5 bridge the contacts 27,

28 and 29. The closing of the -fioat switch closes a circuit from the positive line 30.

through the conductor 31, the float switch 4, conductor-32, switch 33, conductor 34, winding of the solenoid 26, conductor 35, to the negative side 36 of the line. The solenoid 26 then closes the switch 25, which completes the armature circuit, of the motor from the positive side 30, of the line, through conductor 37, 'arm 17, resistance 16,

the winding of the magnet 26. This resistconductor 38, armature 15, switch 25, conductor 35, and back to the ne ative slde. 36

- .of the line. The field circuit or the motor is also closed from conductor 30, conductor -40,'arm 22, conductor 41, field 20, conductor ried on switch 25, and thence by conductor 35, to the negative side ofthe line. The

a solenoid 19, being energized, raises the arm- 17 and gradually cuts out theresistance 16 from the armature circuit, causing'..the mo tor to build up in speed. "When the arm 17 rises, the switch 33 is permitted to open under the action of the coiled spring 46,

thereby inserting resistance 47 in series with ance cuts down the strength of the solenoid 26to such a degree that while it will maintain the switch 25 in its closed position,-it is not of suflicient strength to close the switch in event it drops, it it requires a greater ener to close the switch than to retain it in position after it has once 'been closed.

When the arm.'17 reaches its fullon position, cutting out all of the resistance 16 from the armature circuit, it closes a switch 48, which completes a circuit from the positive side 30 of-the line, throu h conductor 31,. across the float switch 4,. 49, across the switch 48, conductor 50, through the winding 'of the solenoid 23, by

conductor 43, across the switch 45, and by conductor .35,to the negativeside 36 ofthe line.- The solenoid 23 thus being energized,

. raises the arm 22, inserting the resistance 21 ;mits the switch 51 to be-moved by the coiled in the field circuit to' decrease the strength of the 'field, and thereby, increase the speed of the motor.

When the contact arm 22 is raised. it perspring 52, and engage the contact 53, there- .of the solenoid 26, and by conductor 35,,

,rising of the water in the tank'3, the cir-' vfloat switch 4 is opene ma-ins energized through a CllClllli extending by partially short circuiting the float switch In consequencewhenithe water'in the tank 3.is raised to its roper level, and the 5, the solenoid 26 refrom the positive side 36 of the'line, by conductor '40, conductor 54, switch 51, conduc tor 55, 'resistance'47, conductor 34, winding back to the negative side 36 of the line.

When'the float switch 4 is opened, by the cuit through the windingof the solenoid 23 is opened, permitting the arm'22 to descend and gradually cutout. the resistance in the field circuit to slow down the of the motor. When the arm 22 reaches its lowermost position it opens the switch 51, openeing understood that y conductor in the circuit through the winding of the so enoid 26, which in turn permits the switch 25 to open and stop the motor.

system I have eliminated the resistance in the field circuit and control the speed of the motor entirely through the armature resistance. .In the modification illustratedin Fig. 2, a float switch 56 iof the same constrnction as illustrated in Fig. 1 is provided, and the armature resistance--57 of the motor ,is controlled by an arm 58, operated by a solenoid 59. The s eed'at which the arm 58 operates is contro led by a dash-pot 60,

movement of the arm in both directions. A switch 61, having an auxiliar contact 62,

controls the motor circuit an is operated by a solenoid63.

In operation, assumingthat' the water in.

the tank 3 falls below a predetermined oint,

'85; which is so constructed that it retards the then the switch 56 willbeclosed, esta lish- I ing a circuit from the positive side 64 of the line, byconductor 65, across the float switch,

by conductor 66, switch 67, conductor 68.

through the winding of the solenoid 63 i ad by conductor 69, to the negative side 70' of the line. The solenoid 63 is thusener ized and closes the switch 61. and the auxi ia y switch 62. The closinc ofthe, swirziti establishes the armature ircuit of th rjcior from the positive. side of the line; I y conductor 71, arm 58, resistance 57,..cenductor 72, armature 73 of the motor, conductor 74, switch;61, and by conductor 69 to the nega-' tive side 70 of the line.- The field winding of the motor is connected by conductor 75 between the conductors 64 and74 At the same timethat the motor circuit is estab--- lished by the closing of the. switch 62, the

circuit of the winding of the 'solenoid' 59 -is closed from conductor 65, across the float switch 56,- by: conductor 76,: through the winding of the solenoid 59, by conductor 77, across auxiliary switch 62, and by conductor 69 to the ne ative side 70 of the line. The

so enoid 59 thus energized raises the arm 58 and gradually cuts out the resistance 57 from the armature circuit. 'As soon as the .arm 58 leaves the first of'the resistance conthereb placing the resistance .79v in series with t e'solenoid' 63,and atthe same time partially short circuiting the float switch 56, by establishin a circuit from the main 64, by conductors 1 and 8 1,acr,oss the switch ,7

.67, by conductor 8!), through resist rice 79, by conductor 68, through the winding of the solenoid 63, and thence by conductor 69,

the resistance 57 will be slowly inserted in the armature circuit, and the speed of the motor will gradually be diminished.

For the purpose of disclosing the operation of my system, I have described the same in connection with a'motor for operating a pump, and have shown a float switch for controlling the operation of the motor.

, It will be understood, however, that I do ing for operating said member,

not wish to e3 limited to the specific constructioii settgferthyand that various modifications may be used without departing from the spirit of my invention, as for in stance a pressure gage may be used in place of a floatswitch or any other switch mechanism maybe used, if'so desired.

Having thus described my invention what I cla'imas new and desire to secure by Letters'Patent is:

1. In a-motor controlling system, the combination with a resistance, of a controlling member therefor, an electromagnetic winda main switch, an electromagnetic windin for oper ating said switch, a switch operate upon the closure of said main switch for closing the circuit of said first mentioned winding, a

' pressure operated switch adapted, when in one position, to close the ClIGlllt of said sec-v 0nd mentioned winding and in another position to deenergize said first mentioned windmg, and means for maintaining said second mentioned winding ener 'ized until said resistance controlling mem er reaches a predetermined position. I v

2.. In a motor controlling system, the combination witha resistance, of a controlling member therefor, an electromagnetic windin for pperating said member, a main switch, an electromagnetic wmdin for operating said switch,a' switch operate upon the ai i switch for closing the circuit of said rst, mentioned winding, a

closure of said pressure. operated switch adapted, when in a one position, to'elose the circuit of said sec-- o n'd mentioned winding and in another position to denergize said first mentioned winding, means for maintaining said second ment oned'winding energized until said controlling member reaches a predetermined position'and means necessitating saidmember bein in a predetermined 'position, prior. to the e osure of said main switch. I j- 3. In a'motorcontrolling system, the commember therefor, an, electromagnetic win bination with 'a' resistance, of. a controllinlg' ing for operating said member, a main switch, an electromagnetic winding for operatingsaid switch, a switch operated upon the closure of said switch for closing the circuit of said first mentioned winding, a pressure operated switch adapted, when in one posiftion, to close the circuit of said secpnd menytioned winding and in another position to deenergize said first mentioned winding, a re-' sistance arranged to be connected in circuit with said second mentioned winding for rendering the same inoperative to close said main switch, a shunt circuit around said pressure operated switch for maintaining said second mentioned winding energized, and means tending to close said shunt circuit and insert said resistance in circuit, said means being arranged to be automatically operated to open, said, shunt circuit and to short circuit said resistance when said controlling member mm a predetermined position. j

4. The combination with a motor, of an armature resistance controlling device, and a field resistance controlling device, a main switch for the .motor'cireuit, and means for -maintaining said. main switch closed upon the stopping of the motor, until said field resistance device removes all the field resistance from the field circuit. v I v 5. In'a motor controlling system, the combinationwith an armature resistance, an automatically operated controlling member therefor, a field resistance, an automatically operated controlling member therefor, an automatically operated main switch, means insuring the removal of said field resistance from circuit prior to, the insertion of said armature resistance in circuit and means for maintainingsaid main switch closed until the motor speed has been reduced to a predetermined degree.

6. The combination with a motor, of an armature resistance, an electro-responsive device for controlling said resistance, a field resistance, an electro-responsive devicefor controlling said field resistance, and means 'for maintaining the circuit through said armature resistance electro-responsive device in stopping the motor, until after'the field resistance has been removed from circuit.

7. In a motor controlling system, the combination with an armature resistance, of a field resistance, an el ectromagneticalloperated controlling member, for each. 0 saidresistances, an electromagnetically operated main ,switch, a pressure'operated switch adapted, inone position, to cause said main switch to be'c'losed and said controlling nembei-s'to be operated, and in another osition to cause the removal of said fiel resistanee' from circuit, and means ,for -main--, taining said main switch closed man a pre determined amount of said field resistance has been removed from,circuit.

main switch for energizing the winding of the-armature resistance controlling member, 25 2 means automatically Operated upon the insertion of said armature resistance in circuit for energizing the winding of the field resistance controlling member, a pressure operated switch ada ted, in one position to 30 energize the operating winding of saidvmain' switchand in another position to denergizc the operating winding of saidfield resistancecontrolling element, a circuit for maintaining the winding of said main switch 35 energized until the field resistance is removed from circuit and means necessitating tlie insertion of the starting resistance prior to the closure of said main switch,

In witness whereof, .I have hereuntgsub- 40 scribed my name in the'pre'sence of two witnesses.

- g CLARK T. HENDERSON.

" 8. In a motor controlling system,- the combination with an armature resistance, of a field resistance, Ean electroma'gnetically operated controlling, member for each of said 5 resistances, an electromagnetic'ally operated main switch, a pressure operated switch adapted, in one osi'tion, to cause said main switch to be cl dsed and said controlling member to be operated, and in another posi- 10 tion to causet eremoval of .said field resistance from circuit, means for maintaining said main switch closed until said field resistance is removed from circuit and means necessi-' tati ng .the insertion ofsaid armature resist- Maui: 1n circuit prior to the closure of said n switch. In a m tor controlling system, the combination with n armature resistance, of a field-resistance, a controlling member for 20 each ofsaid r' -istances, an operating winding for each Tsaideontrolling members, a Witnesses: p main switch,an operating Winding therefor, -T. E.--BARNUM,

mea ns' operated upon" the closure of said L. D.AR0WEL'L. 

